Unions
Last updated
The query builder also lets you create union statements on your queries using either UNION
or UNION ALL
strategies.
The union
methods take either a Query Builder instance or a closure which you use to define a new QueryBuilder instance.
Union statements are added in the order in which the union
methods are invoked, but the union
statements can be in any order in your API call stack. This means you can safely declare your union
method calls before the select
, from
and orderBy
calls on the source Query Builder instance.
union()
— This method builds a SQL statement using the UNION
clause which combines two SQL queries into a single result set containing all the matching rows. The two queries must have the same defined columns and compatible data types or the SQL engine will generate an error. The union
clause only returns unique rows.
unionAll()
— This builds a SQL statement using the UNION ALL
clause. This is the same as union
but includes duplicate rows.
IMPORTANT: The QueryBuilder instances passed to a union
statement cannot contain a defined order. Any use of the orderBy()
method on the unioned QueryBuilder instances will result in an OrderByNotAllowed
exception. To order the results, add an orderBy()
call to the parent source Query Builder instance.
Adds a UNION statement to the query.
Adding multiple union statements will append it to the query.
It can also add union queries as QueryBuilder instances.
Adds a UNION ALL statement to the query.
Adding multiple unionAll
statements will append it to the query.
It can also add union queries as QueryBuilder instances.
Name
Type
Required
Default
Description
input
Function | QueryBuilder
true
The function or QueryBuilder instance to use as the unioned query.
all
boolean
false
false
Determines if statement should be a "UNION ALL". Passing this as an argument is discouraged. Use the dedicated unionAll
where possible.
Name
Type
Required
Default
Description
input
Function | QueryBuilder
true
The function or QueryBuilder instance to use as the unioned query.